In the cart that I'm working on, I've got a Product that has_and_belongs_to_many :sizes through the table "products_sizes". In my "view_details" action, I need to create a drop down box (select) that lists the sizes the product is available in.
I'm making the sizes of the product available to the action by way of: @product.sizes = Product.find(@params[:size_ids]) if @params[:size_ids]
I just can't figure out how to use "collection_select" or "options_from_collection_for_select" (which I think is old) in order to do that. What's the best current, elegant way to create the drop down?